1. Field of the Invention
The present invention relates to novel processes for preparing highly branched macromolecule polymers that have highly controlled molecular architectures, and which have numerous applications such as chelating agents, rheology modifiers, and drug delivery vehicles.
2. Description of Related Art
The following prior art references are disclosed in accordance with the terms of 37 CFR 1.56, 1.97, and 1.98.
J. Chem. Soc. Perkin Trans. 1992 (p. 2459-2469) discloses a multi-step process for preparing highly branched macromolecules with aromatic polyester inner structure and a readily modified hydrophobic/hydrophilic surface.
Macromolecules 1993, 26, p. 4617-4623 discloses the synthesis of all-aromatic hyperbranched polyesters with phenol and acetate end groups. The synthesis was based on the melt condensation of the A.sub.2 B monomers 3,5(bis-trimethylsiloxy)benzoyl chloride and 3,5-diacetoxybenzoic acid.
U.S. Pat. No. 5,041,516 discloses a multi-step convergent process for preparing polyesters from aliphatic and aromatic monomers.
U.S. Pat. No. 5,136,014 discloses polyesters prepared from aromatic and aliphatic monomers without a core group and which are capped.
U.S. Pat. No. 5,183,862 discloses capped polyesters prepared from aliphatic and aromatic monomers without a core group.
U.S. Pat. No. 5,196,502 discloses the use of diacetoxybenzoic acids and monoacetoxydibenzoic acids to produce wholly aromatic polyesters. This patent does not teach the use of a core monomer to increase the number of surface end groups in the polymer.
U.S. Pat. No. 5,225,522 discloses multiply-branched aliphatic-aromatic polyesters and processes for preparing the same; however, there is no disclosure of a core group.
U.S. Pat. No. 5,227,462 discloses multiply-branched aliphatic-aromatic polyesters and processes for preparing the same; however, there is no disclosure of a core group.